﻿/* Copyright (c) 2009, 2010, John Cronin
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the copyright holder nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */

using System;
using System.Collections.Generic;
using System.Text;

namespace tysila
{
    class StringTable
    {
        public var GetStringAddress(string s, Assembler ass)
        {
            return new var
            {
                label = Label,
                address_of = true,
                local_arg = -1,
                local_var = -1,
                constant_offset = _GetStringAddress(s, ass),
                defined = true
            };
        }

        private int _GetStringAddress(string s, Assembler ass)
        {
            if (str_addrs.ContainsKey(s))
                return str_addrs[s];
            else
            {
                int ret = str_tab.Count;
                str_addrs.Add(s, ret);

                // build the System.String object
                Metadata.TypeDefRow tdr = Metadata.GetTypeDef("mscorlib", "System", "String", ass);
                Layout l = new Layout(new Assembler.TypeToCompile { type = tdr, tsig = new Signature.Param(BaseType_Type.String) }, ass);
                byte[] sso = new byte[l.ClassSize];
                int l_offset = l.GetField("Int32 length", false).OverallOffset;
                ass.SetByteArray(sso, l_offset, s.Length);
                int objid_offset = l.GetField("Int32 __object_id", false).OverallOffset;
                ass.SetByteArray(sso, objid_offset, ass.next_object_id.Increment);

                foreach (byte b in sso)
                    str_tab.Add(b);

                foreach (char c in s)
                {
                    str_tab.Add((byte)(c & 0xff));
                    str_tab.Add((byte)((c >> 8) & 0xff));
                }
                return ret;
            }
        }

        Dictionary<string, int> str_addrs = new Dictionary<string, int>();

        List<byte> str_tab = new List<byte>();

        private string Label;

        public StringTable(string mod_name)
        { Label = mod_name; }

        public void WriteToOutput(IOutputFile of, Assembler ass)
        {
            of.AlignRodata(ass.GetSizeOfPointer());
            of.AddRodataSymbol(of.GetRodata().Count, Label);
            foreach (byte b in str_tab)
                of.GetRodata().Add(b);
        }
    }
}
